MSC1090 - Fall 2021: Assignment 5 part 1b

Hello,

I'm confused about the door Monty will open.

"The number of the door cannot be the door which the contestant has already chosen, nor the door behind which is the car."

Does this mean Monty will never open the door with the car? If so, while contestant chooses switch, the contestant will never get the car. The fraction of winning will be 0.

My understanding may be wrong, Please correct me.

Much appreciate!

Cong

Re: Assignment 5 part 1b - the door Monty open

by Kyla Lee - Wednesday, 20 October 2021, 10:07 PM

Hi Cong, the door Monty opens can't be the door with the car or the door that the contestant chooses, but the door with the car and the door that the contestant chooses can be the same. So yes, Monty will never open the door with the car. If the contestant decides to switch, then depending on which door Monty has opened, they have one other option.

Re: Assignment 5 part 1b - the door Monty open

by Cong Lu - Wednesday, 20 October 2021, 10:59 PM

Hi Kyla,
Thank you for your reply.
I found where I misunderstood. Before I thought the contestant will switch the door with Monty chose.
Now I understand if the contestant decides to switch, the door will be switched to the other door Monty has not opened.